I found out that you can run an active set up with a 4 channel amp. How would you set this up without an active capable hu? How do you send the right amounts of power without overpowering the tweeters and under powering the mids? How do you send the right frequencies to each channel if there's only one input on the smp, or are there two inputs on the 4ch amp?
All you need is one input. You need a active crossover that will separate the frequencies to its desired location. Depending on your amp and the amount of real power it does. I would be very careful when going active. Looking into memphis crossovers, they are by far the easiest to use and if you want better, get a audiocontrol 6xs.
You have 1 input, and depending on the crossover, if its made for 3 way, you will have 6 rca ouputs or 3 pairs (midbass,midrange,tweeters). If you have a crossover for a 2way setup, you will have a Midbass/midrange and a tweeter, 4 rca outputs or 2 pairs.
Does the 4 channel amp have room for two inputs? You wire the signal to to the active crossover, and then from there you have to run an output for the mids into one channel and the output for the tweets into another channel?